a. Field of the invention
The present invention relates to film cartridges and, more particularly, to improvements in a film cartridge for audio-visual projectors.
B. Description of the prior art
In a conventional type of film cartridge for projectors wherein a sprocket means is used to run a film contained in the cartridge, the sprocket means is mostly built in the cartridge. However, in such type of cartridge, there have been defects that the internal structure is so complicated as to be likely to be expensive and that, whenever the sprocket means is out of order, the cartridge will have to be disassembled.